This is a stackable case for Dr Gusman's Pico based Logic Analyser. as detailed here…

https://github.com/gusmanb/logicanalyzer/wiki

The following is directly from the project WiKi…

This is a project to create a very cheap logic analyzer but with capabilities comparable to expensive comercial ones. The analyzer can sample up to 24 channels at a maximum speed of 100 million of samples per second, and it can be triggered via a polarity change in a single channel or a pattern formed by up to 16 channels.

The project does not only comprehend the hardware but also the software, it has a multiplatform application that allows to visualize and analyze the signals. As the device is very unique its protocol is not compatible with other softwares like Sigrok, but the client allows also to export the captured data in a compatible format that can be read by other programs (there is even a cmd application to capture driectly to this format if you don't want to use the GUI application).

The project is based on the Raspberry Pico and it supports its two variants, the regular Pico and the Pico W, so you can even use the device without a physical connection to your computer.

There are two top types for the case, you chose which you want. Just the “Top” can be used as the top of a single case or the top case of a stack. The "Middle" allows other cases to be stacked on top of the case underneith. There is a “Cover” to close off the through pins, if fitted, on a case with through pins fitted to a stack.

Each case can be screwed together with 6 screws, but in reality the case segments friction fit together quite well, so I havent used screws on my stack.

8mm diameter rubber feet can be fitted to the “Bottom” of the case and these help locate a stacked arrangement with the “Middle” section top.